Antenna



A. T. MACE March 7, 1944.

ANTENNA Filed July 5, 1941 ARTHUR T. NWENTOR m W u. m l 8 Pmxwn M El F 4 W AT TOR N EYS Patented Mar. 7, 1944 f ANTENNA Arthur T. Mace,` East Cleveland, Ohio, assignor to The Radiart Corporation, Cleveland, Ohio, a

corporation of Ohio Application July 5, 1941, Serial No. 401,174

6 Claims.

unit to the car quite simple, since no insulation from thecar need be provided for when .using this modified device.

AMoreovery reel operated antennae normally comprise a long flexible member, which upon coiling and uncoiling has a tendency to bind or jam on its confining case, a very serious drawback which has to be met if the antenna unit is to be dependable in use. l

The chief object of the present invention is. therefore, to provide an operating mechanism which will function smoothly and with a minimum of effort without becoming jammed' or locked during use. Another object is the provision of an electrically eicient antenna with completely insulated wire in the aerial proper, at low costs and simple to manufacture.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the annexed drawing and the following description setting forth in detail certain structure embodying the invention, such as disclosed.

In said annexed drawing:

Fig. 1 is a front view partly in section of the assembly antenna unit;

Fig. 2 is a sectional view taken along lines 2-2 of Fig. 1;

Fig. 3 is a rear view of the reel unit, the aerial proper being taken away;

Fig. 41s a side view of the reel unit;

Fig. 5 is a section along lines 5-5 of Fig.` 2; and

Fig. 6 is an enlarged sectional view of a part of the aerial.

Referring to Fig. 1 of the drawing, 8 is a top plate of a metal casting, hereafter called the body casting, having holes 31 formed therein which serve for connection with any desired part of the car or other vehicle designated for carrying the antenna unit. A cup-shaped member 9 is formed onsaid plate 8, with an internally threaded wall, into which an adaptor I0 can be fitted by means of a threadcorresponding to the one in the member 9. A channel Il leads Afrom member 9 into the interior of the coiling device, which channel serves as a passage for receiving or dispensing a cable I2 when coiling or uncoiling of the latter takes place.

Adapter` I0 carries a confining-sheath II which serves 'as a covering for the rubber cable I2 with a core'of piano-wire I3. I choosefpiano-wire because it is of great strength and elasticity. which will both help in smoothly extending the aerial and vkeeping it in position after itk has been extended. This part of the antennamounting is located within a .sheltered place. where a sheath of textile material rwill be sufficient to protect the cable. The covering of the piano wire with the textile material has the further advantage to provide bulk in cross-section which will l help to keep the antenna stable when in the extended position. For theportions of the aerial which are designed to project beyond the walls of the car. a metal tube I5 is provided having arestricted neck portion I6 and an interior shoulder I1 which serves as an abutment for the upper adjacent element. This may be another section of tube or, as shown in the embodiment shown in the drawing, a rod I8.

Within said tube I5 another closely fitting tube 22 is housed, having restricted portions `23 and I9. This tube serves for carrying the cable I3 and moves up and down when the aerial is extended or retracted respectively. Portion I9 is in rigid connection with rod I8 and limits the upward movement of the same when in abutment with shoulder I1. On its upper end the rod carries a ball 20.

Fig. 6 shows the Linner construction of this par-t on an enlarged scale with the outer tube I5 removed. As already mentioned, the core I3 of the cable has a rubber covering I2, which continues up to the shoulder 28 in the `tube 22. Adjacent thereto a tube 29 of Bakelite is provided for enclosing the wire I3 up to its loop-shaped end 26. Said end is embedded in a block of cement 25 which fixes it within the Bakelite tube. The upper end of this insulating carrier is again rformed by a piece of Bakelite, designated by numeral 21, which serves as support for rod I8.

Referring to Fig. 2, a shaft 30 is connected in a manner not shown to a small motor which serves for operating the coiling device. The shaft is located partly in the body casting land partly in a bushing 3l, which fits into a space between said casting and awall 3l of a casting Il serving as an inside drum for thecablewhile it is being uncoiled or coiled respectively. All the castings mentioned in the specification are preferably made of die cast zinc alloy, though other die cast alloys may be used if desired.

One end of shaft is threaded to engage with a stepped hub 34 rigidly connected with a clutch spring 35 in any known manner. The hub is held in position by a pin 32 fitted into a notch 38 of hub 34 (Fig. 4). Spring 35, which is best seen in Fig. 3, is disk-shaped and comprises a plurality of longitudinal slots 36 along its circumference, which serves for holding down a number of suitable elements, for instance balls 39. Said balls are slightly larger than the width of the slots 38 and are thus prevented from slipping through. The balls are accommodated by holes formed in the inner drum 4| at 4U. The clutch spring 35 thus serves for insuring temporary engagement between shaft 30 and the inner drum, while such engagement is desired, viz., during the coiling or ulcoiling of the cable, as will be explained herea ter.

The coiling device proper comprises the inner drum 4I and an outer drum 42 both of which form together a winding reel and are held together by screws 43. 'I'he inner drum is formed by a substantially U-shaped casting, the outer drum by an L-shaped casting. The two drums are assembled in a way to leave a clear space for receiving the wire 45. This space is slightly widening toward the bottom, which helps in properly accommodating the wire.

The mechanism devised for accomplishing the accurate positioning of the wire and preventing the same from getting jammed, consists in a spider having a hub-like central member 46 engaging with a threaded sleeve 50 forming part of the body casting 8. The member 46 carries spokes 41 which are slightly bent downward at their peripheral end where they carry a rim 48. The rim will thus move in a different plane than the hub. the offsetting amounting to the width of one coil winding. The inner drum 4I is provided with slots 53 (Fig. 5) through which the spokes 41 pass freely, thus being enabled to move toward the right side in Fig. 2 during the uncoiling and in opposite direction during the coiling operation, as Will be seen from the description which follows below. One of the spokes 41 carries a slot 55 formed thereon through which the end of the wire is passed and where it remains nxed without any particular clamping means.

The body casting 8 has a sleeve-shaped portion 53 enclosing shaft 30, a clearance of a few thousandths of an inch being provided between said parts to avoid frictional engagement thereof. Moreover, the body casting comprises a rim portion 80 with a ilanged end 6l adapted to close the annular channel between the two drums where the wire is housed. Here too a clearance of a few thousandths of an inch will prevent frictional engagement of part 6| and drums 4I and 42.

The mechanism is operated in the following manner: When the aerial is in its retracted state. the entire length of the cable will be lying wound up between the two drums, the rim 48 will be close to the vertical branch of drum 42, the hub 46 lying adjacent to the vertical portion of reel 4|. The motor is now started and uncoiling of the cable will set in. The body casting with its extensions 50 and 6I remains stationary, While the rotating shaft 30 actuates the two drums 4I and 42 through clutch member 35 rigidly connected by means of hub 34 to said shaft. Drum 4|, while rotating, takes along the rim 48 of spider 46, thus causing the latter to travel along the threaded sleeve 50 in the direction toward the cup S (see Fig. 2). Since the cable 45 is paid out at the same rate as the rim 48 moves in that direction, the latter acts as a support and guide member for the cable during its travel, thus insuring its regular uncoiling without jamming. The front part of the uncoiling cable meanwhile pushes up the end section I8 of the aerial until the portion I9 bears on abutment l1, the aerial being then completely extended. At this moment or shortly after, the movement of the reel ought to be stopped in. order to prevent undesirous torque in said parts. To bring about disengagement of the driven parts even if the motor is still spinning, the clutch connection is provided, which now comes into action. By the increased torque prevailing after the uncoiling of the wire has taken place, balls 39 are forced out of the slots 3B, thus breaking the connection between the driven drum 4l and the driving part, viz., spring 35, secured to shaft 30.

If the aerial is to be retracted the reverse operation takes place, the motor now rotating in the opposite direction. The slot 36 again engages balls 39, both drums being now driven in the opposite directions from the one they had during the uncoiling operation. The hub-part 46 of the spider travels to the left side on sleeve 50 while the cable 45 is supported by rim 48 gradually being moved toward the left side too as the cable advances, the aerial parts being telescoped at the same time. As soon as the rim again bears against part of the drum 42 and can travel no further, the driving action is stopped by disconnection of the spring 35.

While I have described my improved mechanism in combination with an antenna unit normally used in automobiles, it should be under stood that I d0 not want to limit myself to such use since the construction may be applied to any reel operated antenna.

Other modes of applying the principle ol my invention may be employed instead of the one explained, change being made as regards the method herein disclosed, provided the step or steps stated by any of the following claims or the equivalent of such stated step or steps be employed.

I therefore particularly point out and distinctly claim as my invention:

1. In an. antenna unit in combination an aerial, a cable connected to said aerial, mechanism for alternately extending and retracting said aerial while coiling and uncoiling said cable, said mechanism comprising a stationary body casting, a threaded sleeve extending from said body casting, a wheel-shaped member having a threaded hub for engagement with said threaded sleeve. two reel forming drums coaxially mounted with said threaded sleeve and enclosing between them a cylindrical space for receiving the cable upon coiling thereof, one of said drums having slots to receive the spokes of said wheel-shaped member, a rim on said wheel-shaped member adapted to serve as a support and positive guide for said cable while it is uncoiled and coiled, and power means operatively connected to said reel forming drums for driving the same.

2. In an antenna unit for automobiles in coxnbination, an aerial, a cable connected to said aerial, a mechanism for alternately extending and retracting said aerial while uncoiling and coiling said cable, said mechanism comprising a motor-driven shaft, a stationary body casting mounted on but without engagement with said motor-driven shaft, a threaded sleeve extending from said body casting, a-wheel-shaped member' having a threaded hub for engagement with said threaded sleeve, two reel-forming drums coaxially mounted with said threaded sleeve and enclosing between them a cylindrical space for receiving the cable upon coiling thereof, one of said drums having slots to receive the spokes of said wheel-shaped member, a rim on said wheelshaped member adapted to serve as a support and positive guide for said cable while it is uncoiled and coiled, and power means for driving said motor shaft.

3. In a antenna unit in combination, an aerial, a cable connected to said aerial, and a mechanism for alternately uncoiling and coiling said cable, said mechanism comprising a motor-driven shaft, power means to drive said shaft, two rotatable reel-forming drums rigidly connected to each other and adapted to be driven by said shaft, said drums having different diameters thus providing a cylindrical space for housing said cable, an annular guide member mounted coaxially with said drums and adapted to rotate therewith, said guide member serving as a support for said cable While the same is uncoiled and coiled, and clutch means to bring one of said drums into and out of driving engagement with said driven shaft.

4. In an antenna unit in combination, an aerial. a cable connected to said aerial. and mechanism for alternately uncoiling and coiling said cable, said mechanism comprising a power-driven shaft, power means for driving said shaft, a stationary body casting mounted on said shaft, a threaded sleeve extending from said body casting, a wheel-shaped member having a threaded hub for engagement with said threaded sleeve, two reel-forming drums of different diameter coaxially mounted with said threaded sleeve and embracing a cylindrical space adapted to receive said cable, one of said drums having slots to engage the spokes of said wheel-shaped member, a rim on said wheel-shaped member adapted to move in said cylindricalspace and to serve as a support and positive guide for said cable while it is uncoiled and coiled, and torque responsive means having resilient elements therein which serve to bring into and out of driving engagement one of said drums with said power-driven shaft.

5. In an antenna unit in combination, an aerial, a cable connected to said aerial, and powerdriven mechanism for alternately extending and retracting said aerial while uncoiling and coiling said cable, said'mechanism comprising two drums of different diameter for uncoiling and coiling said cable in the cylindrical space enclosed by said drums, an annular guide member mounted coaxially with said drums and adapted to rotate at equal speed, said guide member serving as a support for said cable while the same is uncoiled and coiled, and a torque responsive clutch mechanism comprising a disk-shaped spring having circumferentially spaced slots, said inner of the two drums having holes corresponding in number to said slots for cooperation therewith, and balls in said holes capable of engagement with said slots for operatively connecting said inner drum to said power-driven shaft.

6. In an antenna unit in combination, an aerial, a cable connected to said aerial, mechanism for alternately extending and retracting said aerial while uncoiling and coiling said cable, said mechanism comprising a two-part coiling reel, said two parts being in xed relationship to each other with a cylindrical space formed between them, an annular member rotated at equal speed with said coiling reel, said member being mounted for axial movement with respect thereto for positively guiding said cable while the same is wound onto and ofl said reel within the said 

